[lld] [llvm] [Object][ELF] Support extended header for Object Parser in ELF (PR #162288)

[James Henderson via llvm-commits]

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@@ -556,7 +556,7 @@ Sections:
 # RUN: yaml2obj --docnum=25 %s -o %t25
 # RUN: not llvm-readobj -h %t25 2>&1 | FileCheck -DFILE=%t25 --check-prefix=INVALID-SEC-NUM1 %s
 
-# INVALID-SEC-NUM1: error: '[[FILE]]': unable to continue dumping, the file is corrupt: invalid section header table offset (e_shoff = 0x58) or invalid number of sections specified in the first section header's sh_size field (0x3ffffffffffffff)
+# INVALID-SEC-NUM1: error: '[[FILE]]': invalid section header table offset (e_shoff = 0x58) or invalid number of sections specified in the first section header's sh_size field (0x3ffffffffffffff)
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jh7370 wrote:

Can we lazily populate the information?

One of the issues we've had in the past with llvm-readobj and other dumping tools is it would error out early because it couldn't read some part of the file, long before it actually needed to display the relevant file information, which meant in turn it became hard to impossible to diagnose the problem when a file was malformed in some way. In practice, when we dump the file headers, whether the entire section header table is readable is irrelevant, for example. We should only need to read the 0th section header to do certain things. I hope that makes sense.

https://github.com/llvm/llvm-project/pull/162288